-LRB- CNN -RRB- -- After nearly 15 months being held captive by suspected Islamic militants in the southern Philippines , Warren Rodwell is emaciated , exhausted but delighted to be free at last .

Philippine authorities found Rodwell , a 54-year-old Australian , early Saturday in the port city of Pagadian on the island of Mindanao .

He had been taken hostage in December 2011 , when armed men showed up at the residence where he and his Filipina wife lived on Mindanao .

His captors , believed to be part of the Islamic extremist group Abu Sayyaf , demanded a ransom of $ 2 million , a sum the Australian government refused to pay .

As his detention dragged on , his family and officials in Australia and the Philippines continued to work to try to secure his release .

Their efforts paid off when a Philippine port employee reportedly spotted a sodden and mud-flecked Rodwell trudging ashore in Pagadian before daybreak on Saturday .

Appearing gaunt with sunken cheeks and spindly limbs in photos and videos after his release , Rodwell is now receiving medical treatment .

He was expected to be reunited with his brother and sister , who are in the Philippines .

Relief for the family

`` We 're happy and relieved that Warren has finally been released , '' his sister Denise Cappello said at a news briefing in Manila on Monday .

`` I 'm sure you will understand that this has been a very difficult and exhausting ordeal for Warren , '' his brother Wayne Rodwell said at the same briefing . `` It has also been a difficult time for his family . ''

`` He is delighted to be free , '' he said . `` He has , however , lost a lot of weight and is exhausted . He will need special medical support as well as time and space to recover . ''

Reports in the Australian and Philippine news media suggested that Rodwell 's family had paid a ransom worth nearly $ 100,000 in return for his release .

His brother and sister declined to field questions at the news conference in Manila .

The Philippine government on Sunday said that its policy is not to pay ransoms for victims of kidnappings , the official Philippines News Agency reported .

`` Having said that , we have no information or confirmation on that alleged ransom that was paid , '' Deputy Presidential Spokesperson Abigail Valte said .

A separatist group

Abu Sayyaf , which wants to establish a separate state for the Philippines ' minority Muslim population , has been blamed for several terrorist attacks , including the bombing of a ferry in 2004 that left about 130 people dead , as well as previous kidnappings .

Although the Philippine government agreed a preliminary peace deal last year with the Moro Islamic Liberation Front , a leading rebel group in the country 's restive south , some extremists are still active .

`` We wish the Philippine police every success in tracking down the group that took Warren from his home , '' Cappello said .

`` We hope they will be brought to justice , so others do n't have to experience what Warren has just been through , '' she added .

The Australian government welcomed Rodwell 's release over the weekend , paying tribute to the Philippine government agencies that try to tackle kidnapping cases .

Prime Minister Julia Gillard also acknowledged what his relatives had gone through .

`` Mr. Rodwell 's family have shown a great deal of courage and stoicism in what has been a tremendously difficult situation , '' she said .

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Warren Rodwell was taken hostage in December 2011

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He was released early Saturday , coming ashore in a Philippine port

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His captors were believed to be the Islamic militant group Abu Sayyaf

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His family express relief after `` a very difficult time ''